Automatic circuit-breaker.



Patented Nov. I9, lem.'

No. 686,9la.

H. P. BALL. AUT'DMATIG CIRCUIT BBEAKER.

(Appliution tiled .Tune 25, 1900.)

2 Shasta-Sheet I.

(un Model.)

TL ll nl llll g-lll m ATTGRNEY No. 686,9l8. Patented Nov. I9, I90I. H. P. BALL. AUTOHATIG CIRCUIT BBEAKEB.

(Appumion med :una a5, 1900.)

2 Shasta-Shoot 2.

UNITED STATES PATENT OEErcE.

HENRY PRICE BALL, OF NEWT-YORK, N. Y., ASSIGNOR TO GENERAL INCAN- DESOENT ARO LIGHT COMPANY, OF NEV YORK, A CORPORATION.

AUTOMATIC CIRCUIT-BREAKER.

SPECIFICATION forming part of Letters Patent No. 686,918, dated November 19, 1901.

Application filed June 25, 1900. Serial N0 211451- (NO mdeiJ To all whom it may concern:

Beit known that I, HENRY PRICE BALL, a citizen of the United States, residing at New York city, county and State of New York, have invented certain new and useful Improvements in Automatic Circuit-Breakers, of which the following is a specification.

My invention relates to circuit-breakers of the type which are adapted to automatically break an electrical circuit when the current transmitted through the instrument is in excess of the predetermined amount.

The object of my invention is an improvement in the construction of circuit-breakers by reason of which the automatic operation of the instrument is rendered certain, perfect metallic contact maintained without the employment of knife-switches or other friction devices, and the formation of a dangerous arc or arcs made impossible.

The accompanying drawings will serve to illustrate my invention, and in which similar letters of reference indicate like parts.

Figure l is a side elevation of a double-pole switch with the circuit closed through both poles. Fig. 2 is a front elevation of a doublepole switch with the actuating-magnet in section and with one pole closed and the other pole open. Fig. 3 is a side elevation of a double-pole switch with both poles open. Fig. l is a transverse section of the switchboard and top view of the latch mechanism. Fig. 5 is a detailed view illustrating the position of the laminated contacts when the switch has been opened, but before the inal break of the metallic contacts has been made. Fig. 6 is a perspective View of a single-pole switch of similar construction.

In the drawings, A represents a baseplate, and B B' metallic contact-blocks made of copper or other suitable good conducting material. These contact-blocks are connected to the baseplate by means of the bolts C C',which also serve, through suitable devices common in the art, as a means of connection for the electrical conductors to the instrument. The contact-blocks B B' are arranged in pairs, and the faces of all of the blocks occupy the same vertical plane, which is parallel with the face of the base-plate.

Connected to the base-'plate and situated below the contact-blocks are brackets D. Pivotaliy mounted in the brackets D are the switch-levers E. In Fig. 2 two of such levers are shown. In Fig. 6 one lever is shown. 55

Each of the switch-levers E consists of a pair ot' parallel plates carrying a handle F, ar ranged at an angle to the lever and having a convex protuberance F' on its lower end,

which projects beyond the inner face of the 6o switch-lever. Mounted upon the Vupper end of each switch-leve`risacarbon contactplate G, having a convex upper surface. These plates coact with carbon contact-plates l-I,

having concave under surfaces and elastically supported on spring-plates I, projecting from and secured to the base-plate A and in electrical contact with the contact-blocks B. At the lower end of each switch-leverE and between the parallel plates is arranged a seg- 7o mental bearing-shoulder E', upon which rest the spring-plates I', secured to and in electrical contact with the contact-blocks B'.

In Fig. G, where but a single switch-lever is employed, a pair of vertically-arranged car- 7 5 bons are mounted upon opposite ends of a horizontally-disposed plate E2 and coact with a pair of vertically-arranged carbons secured to the base-plate. The horizontal plate E2 also carries at its end vertically-arranged 8o springs E3, by reason of which the carbons G and H are maintained in good contact when opposed to each other.

Located on the outer end of each bracket D are a pair of spring-plates D', which serve 85 Mounted on and securedto the ends of the piston-rod J3 is a leaf-spring L. This spring for thepurpose of description may be divided into three parts-rst, the inner spring L', which bears upon the opposing surfaces of the contact-blocks B B' and which may conroo sist of one or more plates of resilient good conducting metal; second, the middle spring L2, which bears upon the outer surfaces of the contact-blocks B B and which is composed of a number of superposed layers of resilient good conducting metal, and, third, the outer spring L3, which bears upon the outer surfaces of the contact-blocks B B', but at a distance from and not in contact at its lower cnds with the upper surface of the last layer or leaf of the middle spring or portion L2 and which may be composed of one or more leaves of resilient good conducting metal. The spring L is designed to form three points of metallic contact and by reason of the shape of the inner, middle, and outer portions of the spring to maintain contact with the contact-blocks for different periods of time; or, in other words, the springs L' L2 L0x may be considered as a bridge with three metallic contacts, which will successively make contact when the instrument is closed and break contact when the instrument is opened.

lt will be understood from the foregoing description that when theinstrumentis closed the main portion of the current will be transmitted through the spring L and but a very small portion through the switch-levers E and carbon contacts H G, and that when the instrument is opened the spring L will be projected for some distance forward and out of contact with the blocks B B' by the action of the spring J' and its own resilient eect.

To hold the switch in a locked position and to release the switch, I make use of an electromagnetic device,which l will now describe.

Projecting from the frontof the instrument and in electrical contact at one end with the bolts C and at the other end with the bolts C2 is a solenoid M. Arranged over this solenoid and secured to the base-plate is a bracket N. Located within the solenoid and secured at its ends to the bracket. is a tubular core O. Located within the core O is a tube P, preferably of non-magnetic material. In the upper end of this tube is a perforated plug P', threaded at its upper end and secured to the bracket N. Situated Within the tube P is a metallic armature Q. Mounted over the top of the bracket N and having its stem projecting through the opening in the plug P' is a lifting-pin R. This pin is free to move up and down in the plug P'. Located under the armature Q is a screw Q', adjustable by means of the head Q2, located outside of the tube P, by means of which the limit of the downward movement of the armature may be determined. The screw Q' is longitudinally perforated, and located in such perforations is a rod S, having the upper head S' and lower head S2 situated outside of the tube P. The object of this rod is to give an upward impulse to the armature Q when it is desired to release the switch-levers by hand.

Pivoted to the base-plate A and over the lifting-pin R is a horizontally-disposed rod T, of insulating material. Located over the ends of this rod, on each side of the instrument and between the side plates of the switch-levers, are the pivoted hooks U, pivoted at U' to the blocks B. The outer end U2 of these hooks when the switch-levers are closed take over the horizontal pins Vin the upper end of the switch-levers. Located behind the hooks U are the springs U3, which exert a forward-anddownward movement upon the hooks.

The. operation of my improved automatic switch will be readily understood. Then a current of electricity in excess of a predetermined amount is sent through the instrument, the armature Q is caused to move rapidly upward in the solenoid M. rlhis upward movement is transmitted through the lifting-pin 'R to the rod T, lifting this rod vertically,

which in turn raises the hooks U, thereby releasing the switch-levers E, which are projected forward by the action of the spring J' and the middle and outer portions of the springs L. As the switch-lever E is moved forward the middle portion L2 of the springs L first leaves the contact-plates B B', the outer portion L3 follows, and finally the inner portion L. This breaks the metallic circuit and leaves the circuit established through they switch-levers E and the carbon contacts Il and G. Subsequently by the further outward movement of the switch-levers the circuit is broken through the carbon contacts I'I and G. The levers E finally fall into and between the springs D' on the end of the bracket D, and at the same time the spring-plates l' have left the segmental shoulders E' on the levers E. Manifestly the lifting-pin may be omitted and the armature arranged to impinge directly upon the rod T.

It will be observed that in making the circuit through the instrument before the pins V on the end of the switch-levers E can bc brought under the hooks U the middle and outer portions of the spring L as well as the spring J' must be put under pressure. The effect of this construction is to insure a practically-perfect metallic contact with the contact-blocks and to establish a li ve-spring pressure tending at all times to throw the circuitclosing spring and switch-levers outward, and thus break the circuit. Further, that when the switch-levers are thrown forward at right angles to the base-plate the electrical connection through these levers is entirely severed by the spring-plate I' leaving the segmental shoulders on the switch-levers, (shown in Fig. 3,) therefore avoiding the possibility of the formation of an arc between the levers and the contact-blocks. It will also be observed that in the construction described for a two-pole switch it will be impossible to make a circuit through the switch when the transmitted current is above the predetermined capacity of the switch-4'. c., over load--for if one switch-lever be closed it will immediately dy open when an attempt is made to close the opposite lever. This is a point of great practical advantage.

In this specication l have described two preferred forms of my improved device. I

IIO

l switch-levers to open the circuit, which features I consider to be broadly new with me.

Having thus described my invention, I claim- 1. In an automatic circuit-breaker, the combination of contactblocks, a reciprocating bridge device, an independent pivoted lever, a resiliently-supported carbon contact, and a carbon contact carried on the end of the independent lever.

2. In an automatic circuit-breaker, the combination of pairs of contactblocks, a pair of reciprocating bridge devices, a pair of independent levers, a latch for each lever, a tripping device coacting with both latches, and an electromagnetic device arranged to coact with said tripping device to release the levers.

3. In an automatic circuitbreaker,the combination of contact-blocks, a reciprocating bridge device consisting of two sets of spring contact-plates so arranged that one set will be brought into and out of contact with the contact-blocks before the other set, and an independent pivoted lever arranged to inipart a forward movement to both sets of contact-plates.

4. In an automatic circuit-brealelgtne combination of contact-blocks, a reciprocating bridge device, an independent lever, a latch for said lever, a pivoted insulated bar arranged under the latch, and means for lifting the insulated bar and latch to release the lever. v

5. In an automatic circuitbreaker,the combination of contact-blocks, a reciprocating bridge device, a resiliently-supported carbon contact, a pivoted lever independent of the bridge device, and a carbon contact carried on the end of the independent lever; said parts so arranged as regards each other that in closing the circuit-breaker an electrical circuit will be established between the carbon contacts before the bridge device coacts with the contact-blocks.

6. In an automatic circuit-breaker,the com bination of a pair of contact-blocks, a spring device adapted to reciprocate toward and from said blocks, a pivoted lever, a latch for locking said lever, a solenoid, an armature located in said solenoid, a liftingpin, and a horizontally-pivoted rod located between said latch and said lifting-pin,

7. In an automatic circuitbreake13the combination of apivoted lever havingasegmental bearing-shoulder on its lower end, of a springplate bearing on said shoulder and connected to one of the conductors, a carbon contact mounted on the end of the lever, a carbon contact connected to the opposite conductor, a latch for holding said lever in a closed position, and means for releasing the latch.

8. In an automatic circuit-breaker, a pair of contact-blocks arranged vertically and in line, a horizontally-reciprocating resilient bridge device, an auxiliary resilient device coacting with said bridge device, a pivoted lever independent of said bridge device, and means for locking said lever and holding said resilient bridge device and auxiliary device under tension.

9. In an automatic circuit-breaker, a pair of contact-blocks, a reciprocating bridge device, an independent pivoted lever, a lock for said lever, an electromagnet, a pivoted insulated bar located under the lock, and means energized by the magnet for imparting an upward movement to said bar.

10. In an automatic circuit-breaker, the combination with an independent pivoted le ver, a magnet, a lock for said lever, a pivoted insulated bar under said lock, and means ene ergized by the magnet for imparting an upward movement to said bar.

In testimony whereof I a'dix my signature in the presence of two witnesses.

HENRY PRICE BALL.

Witnessesi J. EPEARSON, W. II. PUMPHREY. 

